The present invention relates to novel controlled release flavoring agents and to processes and apparatus for making and using such agents, and more particularly, it relates to generally solid flavoring agents which can be used to release flavors and aromas in a balanced manner, as for example for foods prepared in microwave ovens.
There is increasingly a need for flavoring agents which provide for a controlled release of flavor during heating or other phases of pre-consumption preparation. For instance, in microwave cooking, because the cooking time is so short, there is not enough time for foodstuffs cooked in microwave ovens fully to develop their flavor. Accordingly, there is a pressing need for flavors which can be added to microwave foods to impart desirable flavors to the foods.
The flavor for addition to microwave foods for cooking in a microwave oven can be a finished typical flavor of that food product or it can comprise precursors which will produce the typical flavor of the food product during the short cooking time. When flavors are incorporated into foodstuffs destined for microwave cooking, the flavors added will be subjected to microwave heating as the food is cooked by microwave. This requires that the added flavor should be able to withstand the microwave heating. While the food is being cooked in the microwave oven, steam is internally generated inside the food, and a steam distillation effect also results. Therefore, the added flavor must be able to remain in the food and not be steam-distilled out.
Encapsulation of flavors has been used in the past. Such encapsulation sought to protect the flavor from oxidation, to prevent it from evaporating, and to convert flavor products in liquid form to solid form. Conventionally, hydrocolloids such as starch, dextrin, maltodextrin, gum arabic, gelatin, and the like are used as the carriers or the encapsulation agents. Products of this type of encapsulation are water-soluble. In the flavor industry, the most common procedures for producing encapsulation products are spray drying, and to a lesser extent, extrusion and coacervation techniques.
For producing water-insoluble products, it has been customary to coat spray-dried powder or some other solid form of the flavoring materials with fat or wax. The application of the fat coating is commonly done by fluidized bed coating or spray chilling. When a spray-dried powder is used as the core material, the process is called double encapsulation.
British Patent 767,700 shows a method for making particles comprising encasing inner articles which contain a fat-insoluble vehicle carrying fat-soluble vitamins in a moisture-resistant substance in which the fat insoluble vehicle is insoluble. U.S. Pat. No. 3,186,909 relates to a method for melting a composition containing fatty alcohol esters derived from sperm whale oil, adjusting the composition to 90.degree. C., adding urea to the composition and dissolving the urea, and adding fish liver oil and vitamins to prepare a homogeneous mixture.
U.S. Pat. No. 3,976,794 shows sweetened coconut products coated with a powdered sugar containing particles of sugar coated in edible fat. U.S. Pat. Nos. 3,949,094 and 3,949,096 show a process for preparing various flavorings, colorants, and flavor enhancers coated with various fats and emulsifiers, the process comprising spraying condiments which are intercepted by a second spray of certain edible coating materials. These prior art processes are capable of only putting limited quantities of flavor material into the finished product.
Except when spice powders or pure chemical powders, such as citric acid, ascorbic acid, and glucono-delta-lactone are used, the flavor loading in the fat-coated spray-dried powders is low, that is, the quantity of flavoring composition in the powder is relatively low. For example, in spray-dried flavor powders, the flavor loading is usually 20 percent. Extrusion encapsulated flavors usually have flavor loading of only 10 to 15 percent. When these powders have an additional coating on top of their original coating, the final loading of the flavor will be reduced still further. Depending on how much fat can be coated on the spray-dried powders, the flavor loading can drop to less than ten percent in double encapsulated powders. A flavor powder with only ten percent active flavor content is of lesser practical interest, unless the flavor is a very powerful one.
Therefore, there is a need for a process to make fat-encapsulated flavor with a high flavor loading and, at the same time, to control or balance the flavor release with the cooking temperature.